Objective To evaluate the feasibility of injectable thermosetting chitosan/glycerophosphate(C/GP)hydrogel as the embolism material of aneurysms.Method 2%chitosan solution and 56%glycerophosphate solution were mixed in different volume ratios.The pH,colloidization time in 37℃and mechanic strength of the mixed solution were detected respectively to determine the best ratio.The intracatheter operation of the C/GP hydrogel by embolizing aneurysm models was evaluated.The C/GP hydrogel histocompatibility was evaluated by embolizing rabbit ear arteries. Finally,we embolized rabbit aneurysm models with this C/GP gel.Results When the ratio of C/GP was 7:1 at pH 7.28,the colloidization time was(260±18)seconds and the mechanic strength chould reach 14 kPa.In the experiment of embolizing aneurysm models in vitro,the C/GP gel could arrive in aneurysms through catheter and reach solid state.In the experiment of embolizing rabbit ear arteries,the modest inflammation was observed.This effect peak was found in 1 week,and gradually resolution in 2-3 weeks.In 4-8 weeks,granulation tissue and slight degradation of C/GP hydrogel could be observed.In the embolism operation of rabbit aneurysms,the aneurysms were disappeared in angiography.In the HE stain slice 3 days after operation,the C/GP hydrogel in aneurysm caves and normal endomembrane cells were observed.There was no significant flame cell in aneurysm walls.Conclusions In short term view,C/GP hydrogel could be used to embolize aneurysms.